This study will evaluate whether the addition of a highly sophisticated and relatively expensive paramedic program in a suburban community can significantly alter the outcome of cardiac emergencies when compared to the basic fire department emergency medical technician (EMT) program presently available. A before and after study design with two control communities will be used. The study will prospectively assess the outcome (death: proximate, intermediate and long-term survival) of cardiac emergencies which occur during 12 months in the study community (population 320,000) presently served by EMTs, a paramedic control community (population 220,000) and a non-paramedic (EMT) control community (population 100,000). The study community will then have paramedic services added and another 12-month prospective assessment of outcome will be made in all three areas.